The present invention relates generally to a method and apparatus for monitoring and controlling vehicle brake systems, and more particularly to a method and apparatus for graphically monitoring and controlling a vehicle anti-lock brake system (ABS) through a selectively connected portable computer or the like for purposes of locating, diagnosing, and repairing brake system faults and for graphically monitoring overall operation of the ABS.
Prior methods and apparatus have been used to monitor and control certain aspects of vehicle electronic systems such as ABS. While graphical tools have existed for monitoring engine-related electronics, prior methods and apparatus for monitoring and controlling an ABS have been primarily text-based systems controllable through a variety of complicated textual input commands such as those commonly used to control DOS-based computer systems. Because these systems had no common "look and feel" or user interface, they required a service technician or other user to be highly skilled in order to effectively and efficiently learn and operate the system. Entry of improper commands, switches, parameters, and other textual input potentially resulted in improper and incomplete brake system diagnosis which, in turn, resulted in improper or unnecessary repairs and/or failure to properly diagnose ABS faults. Furthermore, these systems sometimes required an operator to interpret a large amount of complicated numerical and textual output data regarding the anti-lock brake system--i.e., the output data was not presented in a clear and concise form. While engineers and highly skilled technicians were generally able to interpret such output data, some automobile and truck mechanics not familiar with these prior systems experienced difficulty entering the proper input commands and interpreting the output data without assistance.
Other prior systems are units which are dedicated to monitoring and diagnosing particular vehicle electronic systems--i.e., these prior units have not been usable for any other purpose. Such systems have also been entirely or primarily text-based systems with the above-noted drawbacks and deficiencies. Obviously, such dedicated systems which are usable for only a limited number of purposes increase the cost to service technicians and other users which must purchase these systems for each of a wide variety of vehicle electronic systems.
Vehicles equipped with ABS typically include one or more dashboard lights visible by a driver of the vehicle. The dashboard lights are selectively illuminated to indicate certain ABS conditions to the driver. For example, the lights may be illuminated during vehicle power-up, during an ABS and/or traction control event, and/or in the event of an ABS fault. Prior ABS diagnostic methods and apparatus have not provided convenient and effective means for a technician to test these dashboard lights while also providing a graphical indication of the dashboard light control output from the ABS electronic control unit. The inability to control and/or monitor the dashboard lights renders fault diagnosis more difficult and time consuming.
ABS systems also include an electronic control unit (ECU) carried by the vehicle for controlling the ABS. Certain ECU's, such as those manufactured by AlliedSignal Truck Brake Systems Company, and/or certain diagnostic units selectively connected thereto, may include a series of lights (typically provided by light emitting diodes (LED's)) used to indicate various ABS conditions. For example, illumination of certain LED's on the ECU may indicate proper ECU function while illumination of others may indicate the presence and/or location of ABS faults. The LED's are also used to indicate the ABS and traction control configuration during power-up. Heretofore, there has been no convenient and effective means by which a technician has been able to test the proper ECU control of these LED's and other output lights. In certain cases, it is also very difficult to view the lights provided on the ECU, itself.
Methods and apparatus for ABS monitoring and diagnosis have also not heretofore included means for numerically and graphically displaying the speed of each wheel of the system wherein the data could be (i) recorded, replayed, saved, and loaded; (ii) filtered for display of selected wheel data; and (iii) displayed together with vehicle velocity data. Of course, these prior systems included no means for a technician to view the numerical and graphical wheel speed data together with other graphical ABS data such as current fault data. Likewise, the prior systems have not included means for recording wheel speed data for purposes of graphically displaying same at a later time.
In general, prior ABS diagnosis systems have not been found to be convenient and easy to use, and it has been deemed desirable to develop new and improved methods and apparatus for graphically monitoring and controlling a vehicle anti-lock brake system.